1. The three-phase load current of the generator is unbalanced, and the overloaded single-phase winding will overheat if the difference between the three-phase current exceeds 10% of the rated current, this is a serious phase current; imbalance and the three-phase current is unbalanced. A reverse magnetic field will be generated, thereby increasing losses and causing heating of components such as magnetic pole windings and ferrules. The three-phase load must be adjusted to keep the current in each phase as balanced as possible.
2. The generator does not operate according to the specified technical conditions. If the stator voltage is too high, iron loss increases; the load current is too large, the copper loss of the stator winding increases; is too low, causing the cooling fan speed to increase. It slows down and affects the heat dissipation of the generator; the postmanpower is too low, which increases the rotor excitation current and causes the rotor to heat up. Check whether the indication of the monitoring instrument is normal. If this is abnormal, necessary adjustments and treatments should be made to operate the generator according to the specified technical conditions.
3. The inlet air temperature is too high or the inlet water temperature is too high and the chiller is blocked. The inlet air or water temperature must be lowered to eliminate blockage in the cooler. Before the fault is cleared, the generator load must be limited to reduce the generator temperature.
4. The parallel wire of the stator winding is broken, causing the current of other wires to increase and generate heat. The machine must be stopped immediately for maintenance.
5. The air duct is clogged with dustre and the ventilation is poor, making it difficult for the generator to dissipate heat. Dust and grease in the air duct must be removed so that the air duct is not clogged.
6. If the bearing is filled with too much or too little grease, grease should be added according to regulations, generally 1/2 ~ 1/3 of the bearing chamber (the upper limit is used for low temperatures). speeds, and the lower limit is used for high speeds) ), and should not exceed 70% of the bearing chamber.
7. Bearing wear. If wear is not significant, the bearing may overheat locally; if wear is severe, the stator and rotor may rub against each other, causing the stator and rotor to overheat. Bearings should be checked for noise. If friction between the stator and rotor is detected, the machine must be immediatelyatement stopped for maintenance or replacement of bearings.
8. The insulation of the stator core is damaged, causing a short circuit between the parts, causing an increase in local eddy current loss and heat generation. In severe cases, the stator winding will be damaged. damaged. The machine must be stopped immediately for maintenance.
Hello (Yizhong Power Plant) will answer for you:
If the generator wind temperature is too high, the stator coil temperature, the core temperature of iron and the rotor temperature will increase accordingly, causing insulation to appear. Weakening and weakening of mechanical strength will significantly reduce the life of the generator. In severe cases, this can cause insulation damage, breakdowns and accidents;
Condensation will easily occur if the temperature of the vent is high. too low and water droplets will condense on the generator. The insulation capacity of the generator coil is reduced, threatening the safe operation of the generator.